Howdy,
I'm trying to troubleshoot ways to increase my efficiency and currently I'm focused on how best to accurately measure my mash temp. I use the typical cooler mash tun and a dial thermometer with about an 8-10" stem. I've noticed that after I pitch my strike water and stir thoroughly that my temp can vary quite a bit as I move my thermometer around in the mash. Typically my higher temps are measured at the top of the mash and if I put the stem deeper in the mash I get a lower temp reading. I'm trying to figure out which temp I should go with as I'm fearful of taking my mash temp too high and getting husky astringency. Any thoughts?
Thanks,
Zach
Portland, OR

It can take a while for the mash temperatures to equalize in the tun. I'd recommend trying to stir more, closing up and walking away for 5 minutes, then stirring again and taking the temperature. You should see more even temperatures by then.

What temperature range are you seeing? If you are seeing temperatures like 150F at the bottom and 152F at the top, I'd just consider it 151F. I don't think you should worry about astringency, though, because I don't expect you're seeing any temperatures above 170F.

Thanks for the reply. I've been seeing temp ranges from the low 140's to high 150's and with such a large variance I was having a hard time picking a middle ground to accept.

I think another problem is that I've always done a two-step mash with an initial protein rest at around 125 for 30 mins. It seemed like I was always struggling to get my temp up to 152 following the first rest.

I just tried my first single infusion mash today and temps were much more consistent and I was able to maintain temps of 150 - 152 for the full 60 mins. I think the thicker mash I was working with during the first rest could have potentially been a big part of the problem.

I have been averaging efficiencies of 62-67% and with the use of the single infusion mash I hit a 71%. Quite an acceptable improvement! Additionally, I've also started using rice hulls and 5.2 PH Stabalizer, and so I'm sure that helped a bit too.

You probably don't need the Protein Rest, anyway. I wouldn't be surprised if more volume help to stabilize temperatures. Also, the thinner mash is probably a lot easier to mix well. Thinner mashes also often help efficiency, especially up in the 1.75-2 qt/# range compared to the 1-1.25 qt/# range.